You can check temperature variations using the NOAA/NWS website and changing the location you wish to check. I've done that for Yosemite before going winter camping there. You can see the difference between the Valley floor and Badger Pass for example.
http://forecast.weather.gov/MapClick.php...6000&zone=1

http://forecast.weather.gov/MapClick.php...nit=0&lg=en

Scroll down to the bottom of the page and there is a link to a printable version of just the forecast otherwise, the whole page prints out, which you may or may not want.

Here, in these two forecasts the altitude difference is about 2500 ft. and the temp difference for the coming week is anywhere between no difference and 12 degrees.